Heather Mills's former nanny told an employment tribunal today that she forced her staff to say positive things about her to a film crew, made her work long hours without any extra pay, and caused her to feel uncomfortable by moaning to her about ex-husband Sir Paul McCartney.
Sara Trumble, 26, said her former employer became rude and highly strung after she and the ex-Beatle divorced in 2008.
She also claimed the former model was unsympathetic towards her when she went through a difficult pregnancy, forcing her to accompany her on trips abroad.
Ms Trumble, who was paid £260 a week by Mills, said she felt she was a hard-working and loyal worker but in return her former boss took advantage of her.
Opening her case for compensation before an employment tribunal in Ashford, Kent, Ms Trumble said she met Mills when she came in for beauty treatments where she worked at Hilden Health Club in Rye, East Sussex, in the summer of 2003.
She said Mills, who was living with Sir Paul at his Peasmarsh estate at the time, "was really nice and genuine" at first and when she told her she had been offered another job she asked if she would like to come and work for her instead.
She said her role was not specifically set out but she understood she would be looking after her and Sir Paul's six-month-old daughter Beatrice.
Ms Trumble, who lived with her family in nearby Westfield, said that from April 2004 she was employed to look after Beatrice from 10am to 6pm, five days a week.
However she soon found she was often expected to stay well into the evening while she waited for Mills and Sir Paul to return home from their various engagements, but received no extra pay.
Ms Trumble, who kept a diary throughout much of her employment, said her hours changed as Beatrice grew older and began going to nursery and she was then expected to help with housework as well.
Ms Trumble also said that following the couple's separation in May 2006 her job changed further as custody of the little girl was shared between Mills and Sir Paul and he hired his own nanny to look after her when she was with him.
"Heather was very bitter towards Paul," she said.
"I was, I believe, a great source of comfort and support for Heather at this time."
Earlier the tribunal was delayed due to legal argument over whether information from their divorce proceedings should be used as evidence.
Ms Trumble's solicitor Nick Fairweather argued that the High Court judgment made following the divorce was "highly relevant" as "one of the parties has been found to lie under oath".
Sitting at the back of the hearing room, Mills uttered a long "no" as Mr Fairweather said it should be used as it demonstrated her credibility.
"She (Mills) was found by a High Court judge under the forensic scrutiny of the High Court to have lied," he said.
But Caroline Crampton-Thomas, representing Mills, said using the judgment would "unfairly prejudice" her client.
After considering the matter, tribunal judge Steven Vowles said it should not be used on the grounds of its late disclosure and lack of relevance.
Dressed in a navy blue pinstripe blazer and jeans and wearing black stiletto heels, Mills muttered to her friends throughout Ms Trumble's evidence.
The former nanny is seeking compensation from Mills on the grounds of sex discrimination and unfair dismissal and also claims she suffered changes to her employment terms following her maternity leave.